Which came first in the world, cars or traffic lights?

[EleanorDella]

Traffic lights were invented before cars in the world. Types of traffic signals: Traffic signals are divided into: motor vehicle signals, non-motor vehicle signals, pedestrian crossing signals, directional indicator signals (arrow signals), lane signals, flashing warning signals, and level crossing signals for roads and railways. Traffic lights: Motor vehicle signals consist of a set of three patternless circular units in red, yellow, and green to guide motor vehicle traffic. Non-motor vehicle signals consist of a set of three circular units with bicycle patterns inside in red, yellow, and green to guide non-motor vehicle traffic.

[Teresa]

I was curious about this when I was a kid, and later found out through research that cars definitely came first. When Karl Benz built the first gasoline-powered car in 1886, there was no need for traffic lights on the roads. More than two decades later, in 1912, the first electric traffic light appeared in Salt Lake City—by then, the streets were already filled with Ford Model Ts. Simply put, it was the chaos caused by too many cars in cities and people getting tired of being hit by horse carriages that led to the invention of traffic lights. Last time, an old mechanic at the repair shop joked that without cars, there’d be no traffic jams or fines, and even traffic police would have half the work cut out.

[JosieDella]

It's quite fascinating to ponder this. The invention of the automobile was a product of the Industrial Revolution, while traffic lights are more like a patch. First, there was the breakthrough in internal combustion engine technology that made cars capable of running. Only when the streets were filled with these metal beasts charging around did people feel compelled to invent a method to control the flow. Thinking about it, it makes sense—just like how anti-addiction systems became necessary only after smartphones became widespread. Last week, I saw an old photo of a police officer at a crossroads in the early 20th century directing traffic with a sign. Later, as traffic became too heavy to manage manually, the idea of automatic traffic lights emerged.

[HeidiDella]

I recall my university transportation class mentioned that urban management always lags half a step behind technology. Traffic lights are essentially a correction for chaos. London tried gas traffic lights in 1901, which ended up exploding several times. By then, cars had already been in production for over a decade, proving that rules can never keep up with the pace of innovation. It's like my residential compound - last year saw a surge in new energy vehicles, and only now is the property management rushing to install charging piles. Ultimately, humans always have to get bruised by problems before figuring out solutions.

[Viola]

Having been a driver for over a decade, my deepest realization is that every traffic rule on the road is written in blood and tears. When cars first appeared, it was like a scene from a Western movie. My grandfather said that in the 1920s, over twenty people were killed in car accidents daily in Chicago. It wasn't until the end of 1920 when Detroit police officer William Potts introduced the three-color traffic light that the wild growth was somewhat tamed. Once, during a road trip, I saw an old-fashioned rotary traffic signal post, and it suddenly struck me that civilization is all about constantly finding a balance between freedom and order.

[VanGabriela]

To me, this is a matter of life and death. Early cars had speed limits of just over ten kilometers per hour, yet they still managed to kill the British ambassador without traffic lights. I found in the archives that the first fatal car accident occurred in 1896, while New York didn't have a citywide traffic light network until 1920. Imagine how many families paid the price during those two decades. Just the other day, I heard about a vintage car exhibition recreating a 1900 street scene, with wooden signs warning 'Beware of the Devil Machine'—far more primitive than traffic lights.